Metal slat for venetian blinds



Jan. 29,1935. I c, 1,989,240

METAL SLAT FOR VENETIAN BLINDS Filed July 28, 1932 2 sheets sheet lINVENTOR. WITNESS (kai-Zes NayiZZ- Wat m v g W A TTORNE Y.

c. E. MAGiLL Jan. 29,1935.

METAL SLAT FOR VENETIAN BLINDS Filed July 28, 1932 2 Sheets-Sheet 2 YNVENIZO W/T E55 Cfidflciif a I v ATTORNEY.

slat for use therein.

Patented Jan. 29, 1935 UNITED STATES 1,989,240 METAL sm'r ron vnmrrnmBLINDS Charles E. Magill, Pittsburgh, Pa., Aluminum Company of America,

assignor to Pittsburgh,

. a., a corporation of Pennsylvania Application July as, 1932, Serial N625,278

4 Claims. (on. 156-17) The invention relates to Venetian blindconstruction and to a new and improved form of It is particularlydirected to the provision of a metallic Venetian blind.

The advantages of metal as a substitute for wood in the construction ofVenetian blinds have heretofore been appreciated by workers in this art.It has been proposed to make such metallic blinds from aluminum, chieflybecause of its lightness, durability, and good appearance. The aluminumVenetian blind has not, however, found general acceptance by architectsand builders because of certain disadvantages inherent in the structuresheretofore proposed.

It being recognized that an aluminum or other metal slat for Venetianblinds should possess a certain degree of stiffness throughout itslength, this desideratum has been sought by means of corrugated andflanged designs. Such designs have not been found altogethersatisfactory, however, since they do not possess the desired amount ofstiffness together with the proper degree of flexibility, and inaddition they are somewhat unsightly in appearance. Furthermore, the useof the metallic slat designs evolved prior to the time of the presentinvention has necessitated the development of a new form of supportwhich has led to the proposal of metallic ladder tapes hinged orotherwise secured to the edges of the metal slats. This is an expensiveconstruction and one which is not always desirable. I

It is an object of nw invention to provide a metallic Venetian blindwhich overcomes the disadvantages just enumerated and which combines theadvantages of the metal blind with those of its wooden predecessor. Afurther object is to provide a metal slat for Venetian blinds which issimple in design, easy to fabricate, and

which possesses the general outward appearance of a wood slat.

A more specific object is to provide an aluminum Venetian blind thecomponent parts of which are adapted to the usual type of suspension andwhich at the same time yields the advantages inherent in a brightaluminum surface of high heat reflectivity with low heat emissivity.Other objects and advantages will be quite obvious from a considerationof the design which I have devised, such as greater durability,resistance to deterioration by the elements, and freedom from splittingand warping. I

Certain of these will appear in connection with the followingdescription of a preferred embodiment of my invention in which:

Fig. 1 is a vertical transverse section through a window sash showing myimproved Venetian blind mounted thereon; Fig. 2 is a view to an enlargedscale of the upper end of a Venetian blind installation similar to thatshown in Fig. 1;

Fig. 3 is a perspective view, parts being broken away, showingtheelements of my Venetian blind in partially assembled relationship, theladder tapes and other details of construction being omitted in order tomore clearly illustrate the essential features of my design; and Fig. 4is a fragmentary transverse sectional view through a blind slat takenthrough one of the apertures provided for the lifting cords illustratinga pre-' ferred embodiment of the invention. Figs. 5, 6 and 7 are detailtransverse sectional views through the head bar, tilting bar and bottombar, respectively.

In the drawings likereference numerals have been used to designate likeparts throughout the description thereof.

In Fig.1 the Venetian blind has been shown installed behind aconventional form of sash designated generally by the referencenumeral 1. This construction forms no part of the present invention andwill therefore not be described in detail, it being understood that theVenetian blind as shown is applicable to any of the well known forms ofsash. The blind consists, in its general assembly, of a head bar 2 whichis secured to the sash in anyconvenient manner, as by means of thebracket 3. Below the head bar 2 is suspended by means of brackets atilting bar 4. This tilting bar 4, a bottom bar 5 and intermediate slats6 are secured together in spaced relationship by means of the laddertapes 7.

The usual. lifting cords 8 and tilting cords 9, together with thenecessary sheaves, are provided, and the lifting and tilting -mechanismmay be of the type which is well known to those familiar with the art.

Referring particularly to Fig. 2, it should be noted that the laddertapes 7 comprise side members 10 and cross members 11. The slats 6 restloosely upon the cross members 11 and are guided or positioned by theside members 10. Since the ladder tape is usually made of cloth fabric,it is desirable that the design of the slat be such as to present norough edges or sharp corners to wear or cut through the fabric. To thisend I have conceived the idea of making the slats in the formcharacterized by its flattened seamless tubular cross section withrounded lateral edges 12 for engagement with a ladder tape. The curvedside walls 12 join together the substantially flat upper and lower walls13.

. This design of slat is advantageous from a number of standpoints, .flrst of all from that of,

ease of manufacture. It can be produced from ordinary extruded, drawn,or extruded and drawn aluminum tubing by drawing the same through asuitable die which serves to flatten it out into the form shown. Theresulting article is light and at the same time possesses the requisitestill!- ness so that it will retain its shape and not bend or sag inuse. The smooth edges of the slat which, as has been noted, will not cutthe supporting tapes, give to the slat a smooth appear-- ance closelyresembling that of the wood slat. The bright surface of the metal, whichmay be enhanced by polishing if so desired, possesses the characteristicof high heat reflectivity and low emissivity which renders it peculiarlyadaptable for use in blind construction.

Referring now to Fig. 3, in which the component parts of the blind areshown in greater detail, I prefer to make the tilting bar 4 and bottombar 5, as well as the intermediate slats 6, of hollow construction. Thetilting bar 4 and intermediate slats 6 are provided with elongatedapertures 14 in the upper and lower walls thereof to receive the liftingcords 8. These apertures 14 are elongated in form in order to allow thebars to tilt without interference with the lifting cords. Lifting cords8 are carried up" through a slot 15 in the head bar 2, passing throughsuitable sheaves mounted therein. The

head bar 2 may conveniently be formed of wood ered with the slats in theinclined position there would be likely to be considerable wear on thelifting cords, but this is effectually prevented by the design disclosedin Fig. 4.

While in the interest of clarity I have described my invention withreference to particular embodiments and have employed specific language,I have no intention of excluding any equivalents or minor variations ofthe invention set forth.

I claim:

1. A metal slat for Venetian blinds having a flattened tubular crosssection with rounded latteral edges for engagement with a ladder tapeand being provided with apertures in the flattened walls thereof toreceive lifting cords, the edges of said apertures being flangedinwardly.

2. A metal slat for Venetian blinds having a ,tubular cross section withsubstantially flat upper and lower walls and curved side walls adaptedto be supported on fabric tapes, said upper and lower walls beingprovided with apertures the edges of which are flanged inwardly.

3. A metal slat for Venetian blinds'having a tubular cross section withsubstantially flat upper and lower walls and curved side walls adaptedto be supported on fabric tapes, said upper and lower walls beingprovided with apertures the edges of which are flanged inwardly, theedges of the apertures in the upper wall meeting the edges of theapertures in the lower wall to form tubular guides for lifting cords.

4. A metal slat for Venetian blinds having a flat tubular cross sectionwith flat upper and lower walls connected by curved sidewalls presentinga smooth outer surface, said curved side walls being arcuate in crosssectionand said upper and lower walls tangent with the arc of each sidewall, said flat upper and lower walls arranged in parallelism 'and. inclosely spaced rela@ tionship, and oppositely disposed elongatedapertures in said upper and lower walls.

CHARLES E. MAGILL.

